This invention relates to a method for testing the authenticity of a data carrier. The invention further relates to the data carrier used in said method and to a system comprising the data carrier and an external device.
To prevent unauthorized production and replication of data carriers or the use of such data carriers, it is necessary to be able to test the authenticity of a data carrier with a high measure of reliability. It is also necessary in many cases to be able to test the authenticity of an external device communicating with the data carrier.
A method for testing the authenticity of a data carrier is known from DE 44 19 805 A1. In the known method the data carrier used has at least one integrated circuit with memory units and logical units and a data line for data exchange with an external device. The integrated circuit additionally has a separate hardwired circuit for transmitting and/or receiving data during the power-up sequence. Said separate circuit is used for authenticity testing, the first transmission or reception of data being completed within a defined time domain of the power-up sequence in which no defined state is specified for the data line by ISO standard 7816. Data relevant for authenticity testing are transmitted between data carrier and external device either via a data line on which other data are also exchanged between data carrier and external device or via other lines which do not meet this standard data line and are currently reserved for future applications.